1. Field of the Invention
The present invention relates to a method and apparatus for preventing degradation to unexpected or unintended out-of-spectrum services over copper pairs, while permitting intended services to operate.
2. Acronyms
The following acronyms and abbreviations are used throughout the specification. For brevity, the definitions are summarized as follows:
3. Description of Background Information
Certain levels of service, demanding a certain bandwidth at a certain portion of the available spectrum, are provided over copper pairs providing the physical connection to a telephone company""s Central Office (CO). Typical services available over copper pairs at present include regular analog telephone service (Plain Old Telephone Servicexe2x80x94POTS), burglar alarm service, various types of Digital Subscriber Lines (xDSL) including Asymmetric DSL (ADSL), Digital Data Services (DDS), ISDN service, etc. In the context of the present specification, xe2x80x9ctelephone service linesxe2x80x9d includes telephone lines used for burglar alarms.
Different digital services occupy different portions of the spectrum from each other, and digital services tend to occupy a larger portion of the available bandwidth at a higher frequency portion of the spectrum than regular analog telephone services or burglar alarm services (i.e., low bandwidth-low frequency services). When one service or a set of services is assigned to a customer over a loop (a copper pair), no provision is typically made for support, monitoring, or upkeep of any services over that line other than those assigned.
Accordingly, if a loop intended for one service or a limited set of services (e.g., a low-bandwidth low-frequency service alone, or the same in combination with one or more digital services) is unexpectedly used for an additional service, usually having a different spectrum (e.g., one or more additional digital services), the likelihood of unsatisfactory service is high. That is, no support is provided if the line or loop is used for a service other than those assigned to the loop. Moreover, even if the unexpected use of an additional service over a loop intended for a first service is detected, there is no easily implemented or economical manner of taking remedial action to limit or return the loop to the intended service.
Accordingly, it is one of the objects of the invention to provide an easily implemented, economical method for providing spectral containment over copper pairs at the network side. Moreover, it is a further object of the invention to provide an apparatus for spectral containment useful at the network side.
According to one aspect of the present invention, a method for providing spectral containment over telephone-type service lines, includes selecting a filter having desired spectral characteristics, that passes only frequencies of the desired characteristics. A filter is connected in series to one loop (or more loops), the filter intervening between a loop-plant side and a Central Office side of the loop. Service is then activated over the loop, the filter thereby preventing unexpected transmissions outside of the desired spectral characteristics over the loop.
Optionally, the filter may be connected in series to a loop (or more loops) in a 5-pin module. One pin of the 5-pin module is a ground pin, and the filter intervenes between a loop-plant side and a Central Office side of the module. The 5-pin module may be inserted in a protector block socket in a protector block intervening between the loop-plant side and the Central Office side of the loop.
Alternatively, the filter may be connected in series to a loop (or loops) at a loop plant, the filter intervening between a remote terminal facility and a copper pair side (connecting to, e.g., customer premises) of the loop.
According to another aspect of the present invention, a method for manufacturing a spectral containment unit for preventing unintended or unexpected transmissions, outside of the desired spectral characteristics, over telephone-type service lines, includes selecting a filter having desired spectral characteristics, that passes only frequencies of the desired characteristics. The filter may be connected in series to one loop (or loops) in a 5-pin module, one pin of the 5-pin module being a ground pin, the filter intervening between a loop-plant side and a Central Office side of the module. The 5-pin module is packaged to match a protector block socket in a protector block in a Central Office intervening between a loop-plant side and Central Office side of the loop.
Optionally, a surge protector may be connected in series to the loop (or more loops) in the 5-pin module, the surge protector and the filter each intervening between a loop-plant side and a Central Office side of the module.
Further, the filter may be connected in series between two pins of a loop of a 5-pin plug of the 5-pin module and a remaining two pins of a loop of the 5-pin plug of the 5-pin module. The 5-pin plug is capable of plugging into a 5-pin protector block socket in the protector block. In this manner, the 5-pin module may replace or be formed in combination with a standard module to be plugged into a protector block.
Alternatively, the filter may be connected in series between a 5-pin plug and a 5-pin socket in the 5-pin module, the 5-pin socket being capable of receiving the same 5-pin plug as a 5-pin protector block socket in the protector block. In this manner, the 5-pin module may be placed between a standard module and the protector block.
For either or both of these aspects of the invention, a service to be excluded on the loop (or more loops) may be determined from the group consisting of DDS, ISDN, and xDSL. Then, the filter having spectral characteristics excluding operating frequencies of the determined service is selected. In other words, a service or services assigned to the loop is determined, and a filter that permits substantially only the assigned service(s) is selected.
Alternatively, a frequency range to be excluded on the loop (or loops) is determined from the group consisting of lower than substantially 40 kHz; lower than substantially 80 KHz; and higher than substantially 100 kHz. Then, a filter having spectral characteristics excluding the frequency range and permitting frequencies other than those in the excluded frequency range is selected. In other words, frequencies to be assigned to the loop are determined, and a filter having spectral characteristics permitting substantially only the assigned frequencies is selected.
According to yet another aspect of the present invention, an apparatus for providing spectral containment for preventing unintended transmissions, outside of desired spectral characteristics, over telephone-type service lines, includes a filter having the desired spectral characteristics, that passes only desired frequencies and blocks the unintended transmissions. At least one loop-plant side pair of wires connected to the filter, and at least one Central Office-side pair of wires connected to the filter. A five pin package has two terminals connected to the at least one loop-plant side pair of wires, two terminals connected to the at least one Central Office-side pair of wires, and one terminal connectable to a ground line. The five pin package fits a socket of a protector block intervening between a loop-plant side and a Central Office side of the telephone-type service lines.
According to still another aspect of the present invention, a system for providing spectral containment and preventing unintended transmissions, outside of desired spectral characteristics, over telephone-type service lines, includes a filter having the desired spectral characteristics, that passes only desired frequencies and blocks the unintended transmissions. At least one loop-plant side pair of wires connected to the filter, and at least one Central Office-side pair of wires connected to the filter. A five pin package has two pins connected to the loop-plant side pair of wires, two pins connected to the Central Office-side pair of wires, and one pin connectable to a ground line. A protector block intervenes between the loop-plant side pair of wires and the Central Office side pair of wires at a first point of access of a Central Office. The five pin package fits a socket of the protector block.
Optionally, in these aspects of the invention, the filter may exclude transmissions selected from the group of services consisting of: DDS, ISDN, and XDSL. In addition or alternatively, in these aspects of the invention, the filter may exclude frequency ranges selected from the group consisting of: lower than substantially 40 kHz; lower than substantially 80 KHz; and higher than substantially 100kHz.
The apparatus or system may further include a surge protector connected in series to the loop-plant side pair of wires or the Central Office-side pair of wires. The surge protector and the filter each intervene between the loop-plant side and the Central Office side of the telephone-type service lines.
The apparatus or system may be arranged such that the two terminals connected to the loop-plant side pair of wires include two pins of a 5-pin plug that can plug into a 5-pin protector block socket in the protector block, while the two terminals connected to the Central Office-side pair of wires include another two pins of the 5-pin plug. In this manner, the five pin package may replace or be formed in combination with a standard module to be plugged into a protector block.
The apparatus or system may also be arranged such that the two terminals connected to the at least one loop-plant side pair of wires include two terminals of a 5-pin plug that can plug into a 5-pin protector block socket in the protector block, while the two terminals connected to the Central Office-side pair of wires include two terminals of a 5-pin socket. The 5-pin socket can receive the same 5-pin plug as a 5-pin protector block socket in the protector block. In this manner, the five pin package may be placed between a standard module and the protector block. Further, the 5-pin plug and the 5-pin socket may be formed in the five pin package. As noted above, with this structure, the 5-pin plug fits a socket of the protector block intervening between the loop-plant side and the Central Office side of the telephone-type service lines, while the 5-pin socket receives a protector coil configured to fit a socket of the protector block intervening between the loop-plant side and the Central Office side of the telephone-type service lines.